This invention relates to LED lamps, and in particular to an LED lamp for replacement of directional incandescent lamps, such as spot and flood lamps.
Incandescent lamps are slowly being replaced with more modern lamps, including LED lamps. Low intensity LED lamps can provide efficient light without the need for a large heat sink, but as luminosity increases, providing a practical lamp becomes more difficult, because such lamps are typically designed with massive heat sinks and fins, which affect the aesthetics and functioning of the lamp.
LED lamps are self contained. The power supply for driving the lamps, as well all circuitry, is located within the lamp. U.S. patent application Ser. No. 12/826,774, filed Jun. 30, 2010, the disclosure of which is incorporated herein by reference, discloses an LED lamp replacement for low power incandescent lamps. In that lamp, power consumption is low, and heat dissipation is through a multi-layered printed circuit board and a screw base, with that dissipation being sufficient to keep the LED junction temperature under the maximum rated value set by the manufacturer of the LEDs. Increased power and luminosity, however, require an external sink that dissipates heat that cannot be safely channeled through the lamp screw base.